Choose the correct statement for ${\mathrm{BeCl}}_2\text{ : }$

In solid phase,${\mathrm{BeCl}}_2$ has a chain structure

BeCl2 possesses polymeric chain structure in the solid state. The Be atom is surrounded tetrahedrally by four Cl atoms, two of which are connected by covalent bonds and the other two by coordinate bonds. BeCl2's electron deficiency accounts for its polymeric structure.

In vapour phase, ${\mathrm{BeCl}}_2$ tends to form a chloro bridged dimer

Below 1200K, beryllium chloride exists as a dimer; above 1200K, it exists as a monomer; this monomer is present in the vapor phase because the solid phase is where it polymerized.

Despite having a distinct bonding, Beryllium chloride's polymer structure is identical to that of Be hydride. Halogen bridges are present in both show clustering and halide.

${\mathrm{BeCl}}_2+{\mathrm{H}}_2\mathrm{O}\to {\left[\mathrm{Be}(\mathrm{OH}{)}_2\right]}_n\left(s\right)+\mathrm{HCl}$